POJ 2385

 1 #include <algorithm>
 2 #include <cstdlib>
 3 #include <numeric>
 4 #include <iostream>
 5 using namespace std;
 6 
 7 int max(int i,int j)
 8 {
 9     if(i > j)
10         return i;
11     return j;
12 }
13 
14 int main() 
15 {
16     //freopen("acm.acm","r",stdin);
17     int dp[1005][31];
18     int tree[1005];
19     int T;
20     int W;
21     int i;
22     int j;
23     memset(dp,0,sizeof(dp));
24     cin>>T>>W;
25     for(i = 1;i <= T; ++ i)
26         cin>>tree[i];
27     for(i = 1; i <= T; ++ i)
28     {
29         dp[i][0] = dp[i-1][0];
30         if(tree[i] == 1)
31            ++ dp[i][0];
32     }
33     for(i = 1;i <= T;++ i)
34     {
35         for(j = 1;j <= W;++ j)
36         {
37             if(j > i)
38                 break;
39             dp[i][j] = max(dp[i-1][j],dp[i-1][j-1]);
40             if(tree[i] == j%2+1)
41                 ++ dp[i][j];
42         }
43     }
44     cout<<dp[T][W];
45     return 0;
46 }